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GB.GetRes

Syntax

GB.GetRes(M:IDEAL or MODULE):TAGGED("$cocoa/gb.Res")
    

Summary

returns the resolution computed so far

Description

This function returns the part of the resolution of M computed so far. It does not compute the resolution of M as does Res, rather, GB.GetRes is intended primarily to be used within the Interactive Groebner Framework. Thus, for example, GB.GetRes may be used to examine the resolution as it is computed, one step at a time.

example

    
Use R ::= Q[txyz];
I := Ideal(x^2-yt,xy-zt,xy);
GB.Start_Res(I); -- start Interactive Groebner Framework
GB.Step(I); -- take one step in calculation of resolution
GB.GetRes(I);  -- the resolution so far
0 --> R(-2)
-------------------------------
GB.Step(I);  -- one more step
GB.GetResLen(I);  -- the computed resolution still has length 1
1
-------------------------------
GB.GetBettiMatrix(I);  -- the Betti Matrix so far
----
     
----
   0 
   2 
----

-------------------------------
GB.GetRes(I);
0 --> R^2(-2)
-------------------------------
GB.Steps(I,5); -- five more steps
GB.GetRes(I);
0 --> R(-4) --> R^3(-2)
-------------------------------
GB.Complete(I); -- complete the calculation
GB.GetResLen(I);
3
-------------------------------
GB.GetBettiMatrix(I);
--------------
               
--------------
   0    0    0 
   0    0    3 
   0    0    0 
   0    4    0 
   2    0    0 
--------------

-------------------------------
GB.GetRes(I);
0 --> R^2(-5) --> R^4(-4) --> R^3(-2)
-------------------------------
        
    

See Also